In this case, Yuâ€™s team wasÂ using parathyroid hormone (PTH), which is an FDA-approved treatment for osteoporosis. They administered it, beginning one hour after loss of blood flow, in a mouse model of ischemic stroke. They foundÂ that daily treatment with PTH spurs production of endogenousÂ regenerative factors in the stroke-affected area of the brain. They observed both increased new neuron formation and sensorimotor functional recovery. However, PTH does not pass through the blood-brain barrier and does not change the size of the stroke-affected area, the researchers found.

The conclusion of the paper hints at their next steps:

As this is the first report on this PTH therapy for ischemic stroke for the demonstration of the efficacy and feasibility, PTH treatment was initiated at 1 hr after stroke followed by repeated administrations for 6 days. We expect that even more delayed treatment of PTH, e.g. several hrs after stroke, can be beneficial in promoting chronic angiogenesis and other tissue repair processes. This possibility, however, remains to be further evaluated in a more translational investigation.